update tmux options for removal of old syntax

https://github.com/tmux/tmux/issues/1689

dot/.tmux.conf

@@ -17,35 +17,25 @@ set-option -g allow-rename off
 
 #  modes
 setw -g clock-mode-colour colour5
-setw -g mode-attr bold
-setw -g mode-fg colour1
-setw -g mode-bg colour18
+set -g mode-style fg=colour1,bg=colour18,bold
 
 # panes
-set -g pane-border-bg colour236
-set -g pane-border-fg colour242
-set -g pane-active-border-bg colour236
-set -g pane-active-border-fg colour112
+set -g pane-border-style fg=colour242,bg=colour236
+set -g pane-active-border-style fg=colour112,bg=colour236
 
 # statusbar
 set -g status-position bottom
 set -g status-justify left
-set -g status-bg colour240
-set -g status-fg colour137
-set -g status-attr dim
+set -g status-style fg=colour137,bg=colour240,dim
 set -g status-left ''
 set -g status-right '#[fg=colour232,bg=colour241,bold] %a %m/%d #[fg=colour232,bg=colour240,bold] %l:%M %P '
 set -g status-right-length 50
 set -g status-left-length 20
 
-setw -g window-status-current-fg colour10
-setw -g window-status-current-bg colour241
-setw -g window-status-current-attr bold
+setw -g window-status-current-style fg=colour10,bg=colour241,bold
 setw -g window-status-current-format ' #I#[fg=colour232]:#[fg=colour232]#W#[fg=colour232]#F '
 
-setw -g window-status-fg colour9
-setw -g window-status-bg colour7
-setw -g window-status-attr none
+setw -g window-status-style fg=colour9,bg=colour7,none
 setw -g window-status-format ' #I#[fg=colour0]:#[fg=colour0]#W#[fg=colour0]#F '
 
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